I had to buy an Ecoflow river 2 max because of outages, it was quite good for some time. But as it turned out you have to fully discharge and charge it back every 6 months (if you don't do it, you lose the warranty). I didn't do it, and apparently something happened either with one of the batteries inside or with the sensor that gauges the charge level. I cannot charge it, because it thinks it's 99%, and I cannot discharge it because it's actually 0 and it dies immediately. Previously, I was able to discharge it slowly (it would die but after a while I'd get it to 98, 97 etc) but not anymore. I can't say I wouldn't do it again because I didn't have much choice at the time.
Another thing I bought which I regret is a used system76 laptop. I originally planned to use it during said outages, but battery life is very far from what I expected (I guess it being old and me using linux doesn't help too).
Hey, that's very helpful to know. I'm semi-shopping for a battery to take out for ham radio things - looking at the River 3 and an Anker C300. Haven't dealt with EcoFlow before but Anker has taken care of me on a couple of warranty requests in the past. Thanks for the heads up!
For ham radio, I would strongly recommend buying some 12v LiFePO4 batteries, or a product based on them. It seems many of these consumer "power bank" products (like ecomax) are built on lithium ion batteries, and with that comes much less useful lifetimes, finicky care requirements, and much higher possibility of fire/explosion.
It's pretty easy to convert 12v to anything you might need. Most ham radios will work on 12v. I'm very happy with my DIY setup with 48AH batteries (24AH x2 in parallel) in a harbor freight dry box, some anderson plugs, and a cigarette lighter adapter that I can plug a real AC inverter into, and/or a nice USB PD based charger.
I'm sure there are companies out there that have this all packaged up as a product. I think the key is to look for LiFePO4 batteries.
For the system76 laptop I bet you can replace the battery. They are pretty easy to open up and work on (at least Lemur that I have).